There are four ".swp files" (little guys in blue pants and
pink shirts) on each level. They show up on the radar as blinking
pink dots. You need to rescue them by picking them up. Cron
jobs (green robots) will try to abduct the .swp files and
carry them off to the volcano to be incinerated. You should
shoot the cron jobs to prevent this. Once you've collected all
four .swp files, head to the right hand side of the level where
you'll find a socket which you can fly into which will take you
to the next level. (You don't have to save all four (or any)
.swp files int order to use the socket, but if you don't, you
won't get the full allotment of bonus points.)

Use the arrow keys to move, 'z' to fire the laser, 'b' to
drop bombs.

Why is it so hard?

Have you ever played Defender? This game is easy, not hard.
Defender is hard. Get a wired USB Xbox 360 game pad.
It makes the game much better.

Does Word War vi work on Windows?

No. However, it would probably not be very hard to port.
The libraries it uses -- gtk, libvorbis, and portaudio are all
already available to Windows. The joystick support is currently
linux-specific however, but the game can be played without
joysticks. If you try porting it, let me know how it goes.

Are there binaries available?

Not from me. Check your distro, there may be binaries available
from the official repositories for Fedora, ubuntu, gentoo, and the
like. Or compile it yourself.

Why does the screen saver activate during the game when playing
with a joystick?

Ask the screen saver guys (xscreensaver, gnome-screensaver,
kscreensaver) why they have three different ways for an app
to disable "the" screensaver. When there's one way
to disable it, then maybe this problem will go away. Until
then, deal with it.

Why do the graphics suck so bad?

They don't. You are just handicapped with bad taste.

I'm not comfortable playing a game in which I'm asked to
shoot at "Stallman's Airship." RMS is my hero! What should I do?

You should take notice of how many points are awarded for
shooting Stallman's airship.